SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07819334f8b62655f229155c08310a0b82ae779d8f970e34c3178be289463e1b' 
  AND token = 'uWYLwK0S3MOqyZ17gEbTaJT6spnsksraXBw+HaA2SxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}